Pipes?!…
One of the most curious, and strange, web applications that appeared in this thing we call Internet has to be Yahoo! Pipes. In just a few words, but Lifehacker have a more detailed review, this tool lets you gather information from several places around the web (usually using RSS), transforms it and exports the results into one place. The best part is that this happens using a neat graphic interface, no HTML code or technical knowledge is needed, I just used it for a couple of minutes but I already created something I was needing for some time: a way to combine the updates of my photo galleries in one place, usefull for publising it as a RSS feed.
[update] Frantic Industries has a nice article about Yahoo! Pipes.
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